Known types of liquid crystal display devices include vertical electric field display devices and lateral electric field display devices.
Vertical electric field display devices apply substantially vertical electric fields to liquid crystal molecules through a pair of electrodes with a liquid crystal layer therebetween. Different modes of vertical electric field liquid crystal display devices such as TN (twisted nematic) mode and VA (vertical alignment) mode exist.
The lateral electric field mode liquid crystal display device has a pair of electrodes insulated from each other provided on a liquid crystal layer side of one of a pair of substrates sandwiching the liquid crystal layer. The lateral electric field mode liquid crystal display device applies a substantially lateral electric field to the liquid crystal molecules. The modes of lateral electric field liquid crystal display devices include IPS (in-plane switching) mode and FFS (fringe field switching) mode.
Patent Document 1, for example, discloses a structure of an FFS mode display device in which a pixel electrode and a common electrode are disposed on the liquid crystal layer side of the array substrate such that the pixel electrode and the common electrode face each other across the interelectrode insulating film, which is formed of an inorganic insulating film.
A passivation film made of an inorganic insulating film is formed on the array substrate and covers the semiconductor layer. An interlayer film made of a resin material is formed so as to cover the passivation film. A pixel electrode is formed on the interlayer film. The interelectrode insulating film covers the pixel electrode on the interlayer film.